libstdc++
pod_char_traits.h
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1 // POD character, std::char_traits specialization -*- C++ -*-
2 
3 // Copyright (C) 2002, 2003, 2004, 2005, 2007, 2009 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file ext/pod_char_traits.h
26  * This file is a GNU extension to the Standard C++ Library.
27  */
28 
29 // Gabriel Dos Reis <gdr@integrable-solutions.net>
30 // Benjamin Kosnik <bkoz@redhat.com>
31 
32 #ifndef _POD_CHAR_TRAITS_H
33 #define _POD_CHAR_TRAITS_H 1
34 
35 #include <string>
36 
37 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
38 
39  // POD character abstraction.
40  // NB: The char_type parameter is a subset of int_type, as to allow
41  // int_type to properly hold the full range of char_type values as
42  // well as EOF.
43  /// @brief A POD class that serves as a character abstraction class.
44  template<typename V, typename I, typename S = std::mbstate_t>
45  struct character
46  {
47  typedef V value_type;
48  typedef I int_type;
49  typedef S state_type;
51 
52  value_type value;
53 
54  template<typename V2>
55  static char_type
56  from(const V2& v)
57  {
58  char_type ret = { static_cast<value_type>(v) };
59  return ret;
60  }
61 
62  template<typename V2>
63  static V2
64  to(const char_type& c)
65  {
66  V2 ret = { static_cast<V2>(c.value) };
67  return ret;
68  }
69 
70  };
71 
72  template<typename V, typename I, typename S>
73  inline bool
74  operator==(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
75  { return lhs.value == rhs.value; }
76 
77  template<typename V, typename I, typename S>
78  inline bool
79  operator<(const character<V, I, S>& lhs, const character<V, I, S>& rhs)
80  { return lhs.value < rhs.value; }
81 
82 _GLIBCXX_END_NAMESPACE
83 
84 _GLIBCXX_BEGIN_NAMESPACE(std)
85 
86  /// char_traits<__gnu_cxx::character> specialization.
87  template<typename V, typename I, typename S>
88  struct char_traits<__gnu_cxx::character<V, I, S> >
89  {
90  typedef __gnu_cxx::character<V, I, S> char_type;
91  typedef typename char_type::int_type int_type;
92  typedef typename char_type::state_type state_type;
93  typedef fpos<state_type> pos_type;
94  typedef streamoff off_type;
95 
96  static void
97  assign(char_type& __c1, const char_type& __c2)
98  { __c1 = __c2; }
99 
100  static bool
101  eq(const char_type& __c1, const char_type& __c2)
102  { return __c1 == __c2; }
103 
104  static bool
105  lt(const char_type& __c1, const char_type& __c2)
106  { return __c1 < __c2; }
107 
108  static int
109  compare(const char_type* __s1, const char_type* __s2, size_t __n)
110  {
111  for (size_t __i = 0; __i < __n; ++__i)
112  if (!eq(__s1[__i], __s2[__i]))
113  return lt(__s1[__i], __s2[__i]) ? -1 : 1;
114  return 0;
115  }
116 
117  static size_t
118  length(const char_type* __s)
119  {
120  const char_type* __p = __s;
121  while (__p->value)
122  ++__p;
123  return (__p - __s);
124  }
125 
126  static const char_type*
127  find(const char_type* __s, size_t __n, const char_type& __a)
128  {
129  for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
130  if (*__p == __a)
131  return __p;
132  return 0;
133  }
134 
135  static char_type*
136  move(char_type* __s1, const char_type* __s2, size_t __n)
137  {
138  return static_cast<char_type*>
139  (__builtin_memmove(__s1, __s2, __n * sizeof(char_type)));
140  }
141 
142  static char_type*
143  copy(char_type* __s1, const char_type* __s2, size_t __n)
144  {
145  std::copy(__s2, __s2 + __n, __s1);
146  return __s1;
147  }
148 
149  static char_type*
150  assign(char_type* __s, size_t __n, char_type __a)
151  {
152  std::fill_n(__s, __n, __a);
153  return __s;
154  }
155 
156  static char_type
157  to_char_type(const int_type& __i)
158  { return char_type::template from(__i); }
159 
160  static int_type
161  to_int_type(const char_type& __c)
162  { return char_type::template to<int_type>(__c); }
163 
164  static bool
165  eq_int_type(const int_type& __c1, const int_type& __c2)
166  { return __c1 == __c2; }
167 
168  static int_type
169  eof()
170  {
171  int_type __r = { -1 };
172  return __r;
173  }
174 
175  static int_type
176  not_eof(const int_type& __c)
177  { return eq_int_type(__c, eof()) ? int_type() : __c; }
178  };
179 
180 _GLIBCXX_END_NAMESPACE
181 
182 #endif
_OI fill_n(_OI __first, _Size __n, const _Tp &__value)
Fills the range [first,first+n) with copies of value.
Definition: stl_algobase.h:785
A POD class that serves as a character abstraction class.
ISO C++ entities toplevel namespace is std.
long long streamoff
Type used by fpos, char_traits, and char_traits.
Definition: postypes.h:94
GNU extensions for public use.
Class representing stream positions.
Definition: postypes.h:112
Basis for explicit traits specializations.
Definition: char_traits.h:231